I'm finally getting a greenhouse

A greenhouse has been on our homestead master plan for over a decade. To be honest, there were times when I thought it would never become a reality. But at last! I'm finally getting a greenhouse.

Choosing a good location was one thing that took time because we have so many mature trees on our property. So finding a convenient spot with enough sun was a consideration. One idea we tossed around for years was to build it off this side of the house.



I thought it would be extremely convenient, with the added benefit of helping to warm the house in winter. The disadvantage would be trapping hot air in summer and humidity with potential mildewing the siding of the house. But with good ventilation, we reasoned, we could deal with that.

I knew things were getting serious when my husband Dan finally cleared away the old bushes in front of the windows and removed a pecan tree and some shrubery that shaded the spot.



The building plan was to use as many homegrown and recycled materials as we could manage. We saved all the old house windows over the years as we replaced them with energy efficient ones.



Preperatory tasks included leveling the ground where we'd dug out the shrubs, and taking down that section of our backyard privacy fence. This is where the back wall of the greenhouse will be.



Then we could begin the build.

I'm excited for you! What a dream come true once it is built. I'm envious.

It always amazes me how long it can take to decide to do something, yet once the decision is made, the action comes pretty quickly.

The ground where we decided to put the greenhouse slopes gently from front to back. For the foundation, Dan decided to pour a concrete retaining wall at the back, and use gravel and cap blocks for the front and side. We live in the southeastern US, where the ground rarely freezes so frost heave isn't a concern.  The pictures should explain it better than my words can.

Oh wow congratulations. I know this will be a great joy. I grew up with a large commercial greenhouse and tho it’s been almost 20yo area since we had it I miss it still.

So nice to walk into in the fall / winter. Heck I even liked it in the summer with 2 huge fans pulling air through.

I love having a greenhouse! But I would suggest you design it such that you can remove a good portion of the glazing in summer. My greenhouse is attached to my house and is the primary source of heat for the house. It's just a big UV resistant plastic sheet and we put it up in October and take it down in May. If it stayed up in summer, the plants would be killed and the house would be unbearable.

Shading and ventilation can only do so much in summer if a greenhouse is in the sun. Being able to remove panels seems much more effective.

Rebecca, that's a good idea. We'll see what Dan has in mind! I will say that I've assumed I won't use the greenhouse in summer because of our hot climate. So I'm planning on fall and winter growing, and early spring seed starts. Good ventilation will be a must.

In my first post I mentioned we want to use as many recycled and home sourced materials as possible. One of the things we've been able to home source is most of our lumber. Several years ago Dan found a sawmill on Craigslist and bought it. I have to say that it has been an excellent investment. About half of our property is wooded, and as we've thinned out pines and oaks, Dan has been able to mill our own lumber to use in our numerous building and remodeling projects. It's not the biggest or the heaviest sawmill out there, but the price was right and it's served us well. It's more than paid for itself.



He squares the logs as he cuts them and lets them cure. When we have a project, he mills what he needs from the cured logs.



After that, he got busy on the framing.





In the meantime, we sourced materials for the roof, which is next.

I grow tomatoes and chiles in mine all summer,they love it! Of course the door and the back end are open for air flow,but i do not get any blight issues because they never get rained on, i only hand water so its and extra chore but the tomatoes are always nice and grow like mad.Just open the windows if you are using those in the photos. Your climate my be warmer than mine so grow your usual plants as normal and experiment with the greenhouse the first couple years,i dont want you to lose them if you only have them in the greenhouse!

For roof windows, we had two sources. One was Craigslist, the other was a builders surplus supply warehouse. We bought all of our new house windows there for a fraction of retail. Dan couldn't find enough of one type for the entire roof, but he found some heavy windowed wood doors on Craigslist and a set of windows from the warehouse.







The doors would go in the top section, and the windows in the bottom.





We wonder if it looks a little haphazard, but figured if we could keep placement symmetrical, it would hopefully look like it was planned that way!

I'm so glad for you!  I would love to someday have a greenhouse, specifically for growing tropical/subtropical fruits/veg and we'd move the plants in their huge pots out in the warm months and into the green house in the cold months, so I'd likely want one which can be dismantled like Rebecca was talking about.  I'm excited about your progress!

Dang! Y’all aren’t playing around. You have a greenhouse in a day or two now lol. I think it doesn’t look bad. Repurposing or reusing gets a thumbs up in my book. Now you’ve done two good things at same time.

Thanks Joe! The choice of building materials has been an important consideration.

I should mention too,that I'm not posting in real time. It's taken me awhile to sort the pictures, choose the best ones, and prep them for the internet. Just like the actual work being done on the greenhouse, posting about it is done in streaks!

We couldn't find enough of any one type of used or surplus windows for the entire greenhouse roof, so the upper and lower sections are different.



The window panels came with vinyl framing, which Dan removed. Then they were slipped under the wood frames of the windows in the top section.



The panels were all the same size, but some had mullions between the two layers of glazing and some didn't.

Here's how it looked from inside the greenhouse.





Hopefully, it looks like it was designed this way.

Leigh, how will rainwater drain off the upper row of windows that appear to be in wood frames? Only evaporation? There will also be condensation on the lower surface that might run downwards to the wooden frames though maybe with the low angle it will just stay in place.

Riona Abhainn wrote:... specifically for growing tropical/subtropical fruits/veg and we'd move the plants in their huge pots out in the warm months and into the green house in the cold months, so I'd likely want one which can be dismantled like Rebecca was talking about.  

Yes, I grow a few perennials that wouldn't survive outdoors in our cold winter like a local variety of seedless green grapes that I'm a little too high altitude for, and rosemary. The small asparagus bed in the greenhouse produces in Feb-March, where as the big outdoor beds produce in April-May, but the Feb-March fresh asparagus is hugely appreciated. Likewise the perennial scallions, and perennial flowers and bulbs.

Because I remove the glazing entirely for summer, the grapes, rosemary, asparagus and other things are in the open air all summer and do fine. If I had the glazing on and just the ends open, in this high desert sunny climate I think those would be cooked and killed. In some climates having the ends open would be good enough I guess.

I also have variety of other things in the greenhouse: annual leafy greens all winter of different types that wouldn't survive outdoors; and other perennials and herbs that can bloom or produce earlier in the greenhouse than outdoors. Plus it's great for spring starting seeds.

Rebecca Norman wrote:Leigh, how will rainwater drain off the upper row of windows that appear to be in wood frames? Only evaporation? There will also be condensation on the lower surface that might run downwards to the wooden frames though maybe with the low angle it will just stay in place.

Rebecca, I had the same questions and when I posed them to Dan he said this was how his parent's greenhouse was constructed and they had no problems. The windows have been caulked and sealed, so now it's a matter of wait and see what happens when it rains.

As an aside, I have to mention that a valuable lesson we learned early in our homesteading was to consider everything an experiment. We've learned to expect problems and when they arise, we can say, "well, it's an experiment, so how to we correct this problem? How can we improve on this idea?" So much of what we do is a work in progress.

Congratulations on your new greenhouse!  Thanks for sharing the excellent build!  It looks amazing!

Someone's building one with reclaimed windows in my region too, I hope they'll pitch the roof steep for snow.  I gather you don't have much snow where you are.  So good to see stuff being repurposed.

Try to make it rodent proof and have plenty of ventilation.  I absolutely hated having rats eat my tomatoes, and then my tomatoes AND each other when I put in traps.  The newest greenhouse is 3 years rodent free so far,  so I am very happy. I have fine wire mesh over any opening windows and a sliding patio door to enter it.  I never leave that door open.

Joshua Myrvaagnes wrote:I gather you don't have much snow where you are.  So good to see stuff being repurposed.

Joshua, you're correct. We typically get one snow event per winter with a couple of inches melting by the next day. That's a good point, though, about roof pitch in snow country.

Brian White wrote:Try to make it rodent proof and have plenty of ventilation.  I absolutely hated having rats eat my tomatoes, and then my tomatoes AND each other when I put in traps.  The newest greenhouse is 3 years rodent free so far, so I am very happy. I have fine wire mesh over any opening windows and a sliding patio door to enter it.  I never leave that door open.

Gosh, rodents would be very unwelcome, and we definitely live in rodent territory. So far, two of our cats really like hanging out in the greenhouse. Good points about screening and mouse entry places.

I am planning to build a similar small greenhouse attached to the east wall of my house. I want it primarily for winter and shoulder season use. I plan to use a regular/ non-glazed roof because I just want the low-angled morning light, not the blazing summer sun. In summer, I hope it will be more like a sun room or conservatory than a greenhouse. I'm in southern Indiana, zone 6b.

Rita, that's an excellent idea. Bill Mollison talks about using the roof and seasonal angle of the sun to maximize warmth in winter and cooling in summer. Before we started building, we observed the seasonal changes of the sun on this spot to make sure the location would work. I think the observations were worth it.

To open or not to open. That was the question for the repurposed windows to be used for the greenhouse walls. The plan has always been to use our old house windows, but most of them were in pretty bad shape, so the sashes had been removed from their original casings. With that, we had a lot discussion about whether or not the windows should open. Several factors went into the decision making process.

One was my experience with our hoophouse several years ago. It was my first experiment with a greenhouse, and we covered it with plastic sheeting. This worked well except that our winters tend to be quite mild. On warm days (in the 60s) the hoophouse was very hot, even when I opened both ends and rolled up the sheeting a bit. It still trapped a lot of warm air so that all of my fall and winter veggies bolted.

The other big question was, how complicated do we want to make this? Over the years we've learned how easy it is to make elaborate plans when we're excited about something. But Dan really wanted to keep construction simple, so we had to brainstorm about ventilation. Especially for summer. Because of my hoophouse experience, I had already reckoned that the greenhouse would be too hot for growing much in summer. So from the get-go, I've been thinking it will only be for fall and winter growing and spring seed starts.

It was during one of our brainstorming sessions that we came up with the idea of using the old jalousie windows we removed from the back porch when it became my summer and canning kitchen.

front of greenhouse with first jalousie window

They are screened and crank open, and we have two of them. By putting one on the front wall and one on the back wall, we hope to catch the breezes that flow that way.



Something else we decided on is a solar attic fan. We have one in our attic and it really helps.

So that's the plan. How well all this works remains to be seen. I'm counting on this first year to be experimental anyway, which future adjustments made on what we observe.

long side wall ready for the windows.

Because you plan on experiment and adapt you may find that you want to make the upper roof windows open instead of depending on a fan.  If there is too much summer sun entering the house windows then an openable solid roof may an even better choice.

Hans, interesting you should say that. Originally, I wanted to use the jalousie windows on the roof, but Dan couldn't work it out for a smooth fit with the other windows he used on the roof. Of course, when our summer days hit the 90s, I not so sure anything will help.

Next will be trims and paint (weather permitting).

That's beautiful!

Leigh Tate wrote: Of course, when our summer days hit the 90s, I not so sure anything will help.

The glass roof will give more light into the house windows during the winter. You could consider getting some sort of shade cloth or semi-rigid material to cover the greenhouse roof during the worst of the summer. The trouble with this plan is that anything that doesn't tolerate a lot of UV won't last long, but if you only put it up June to Sept, and store it out of the sun the rest of the year, it might be worth the bother.

Leigh, I LOVE this!! It's something I've always dreamed of - then, we bought a house with a drop-off, 6ft from the south side of the house, lol. So, I'm really enjoying yours!

Carla Burke wrote:... we bought a house with a drop-off, 6ft from the south side of the house, lol.

Hmmm... A tiered garden with rock retaining walls and the beds about 3 ft wide? Earth sheltered at least?
That said, I've seen pictures of your idea of a "drop-off" and "cliff" might be a closer description?

Jay Angler wrote:The glass roof will give more light into the house windows during the winter. You could consider getting some sort of shade cloth or semi-rigid material to cover the greenhouse roof during the worst of the summer. The trouble with this plan is that anything that doesn't tolerate a lot of UV won't last long, but if you only put it up June to Sept, and store it out of the sun the rest of the year, it might be worth the bother.

Shade cloth is exactly what I've been thinking. That room that the greenhouse is attached to is always the hottest room in the house in summer, anyway, so any kind of shading would help. I may have to do some experimenting this summer, to try and find the simplest solution that works.

Jay Angler wrote:

Carla Burke wrote:... we bought a house with a drop-off, 6ft from the south side of the house, lol.

Hmmm... A tiered garden with rock retaining walls and the beds about 3 ft wide? Earth sheltered at least?
That said, I've seen pictures of your idea of a "drop-off" and "cliff" might be a closer description?

🤣😅I figure if I can traverse it with no more than trees & their roots, for foot & hand-holds, it's a drop-off. If I need rappelling gear, it's a cliff, lol. But, yeh, it's steep - but that one is pretty shallow, and a relatively short drop, compared to most of them, here - and, yup - trellis is the plan, and there might be a greenhouse on one level, but, not attached to the house.

I'm enjoying your posts, and your journey.  I have been building a greenhouse too. Mine is not attached to the house, has taken a very long time.  I have been waiting to post mine until I'm finished.
It will be interesting to see how you decide to deal with the summer heat.  Like you I don't think I will use mine in the summer. I have lots of ventilation, and thinking about getting shade cloth. The attic fan is a good idea. I've been looking for a solar fan, and can't find one big enough to do the job, and  is still affordable.  
I'm looking forward to seeing the finished greenhouse.  So far it looks amazing.

Jen, thank you! I'll be interested in seeing yours when you get it posted.

I think I'm almost more concerned about heat in summer than in winter cold. We live far enough south that I'm thinking I can grow enough cool weather veggies to make it worth my while, but heat stacking up in summer is a concern. The vent fan should help. And I like the idea of somehow using shade cloth. Just have to figure that one out.

With the roof and walls up, we needed a door.



We didn't have one to recycle like we did for all the windows, but we did find a reasonably priced one at an area builder's surplus supply warehouse.



A sliding door made the most sense (to me!), so with sliding door hardware, Dan made it happen.





The only thing I'm concerned about is the track for the bottom of the door.



How in the world am I going to keep that cleaned out???

You could cut the end of the track off where it meets the corner there in the picture,trench the soil back away from that area and rake anything that gets in there out with a brush or stick or even your finger.It will act as a clean-out for the track.

You could also build a trench a few inches back from the track and place a barrier plank higher than ground level to hold back any debris that might get kicked into it,this could cause a tripping hazard though.It would be a U-shaped trench with the door and track sitting inside of it.

One of the first tests, was whether or not the roof leaked. Dan used a highly rated popular sealer on the seams, but alas, it wasn't all it was cracked up to be. Even after reapplying several times. We ended up covering the top section of the roof, where the leaking problem persisted with the framed windows.



These "roofing" panels are pretty flimsy, but they don't block the light and they've fixed the problem.

With the walls and roof all up, my greenhouse can now get pretty warm on sunny days! Installing the vent fan was next.



This is the side of the greenhouse that gets the afternoon sun. Locating the fan on this side means we can draw air from the shadier back side through the jalousie window and exhaust warmer air out the front.



It's an 12-volt 80-watt solar powered fan. Dan is attaching it to a 100-watt solar panel on the roof.

Here it is with all the wall trims.





The vent cover was original to the attic. We replaced the attic vent covers when we put the new siding up. We saved everything we took out, and this one fit perfectly!

Here's how it looks on the inside.



I wanted to be able to turn it off if needed, so Dan installed a switch for me.



I don't want it running on really cold days, but on mild sunny days, we need it.

And it's working! When the outside temp got to 52°F (11°C), the greenhouse thermometer read 80°F (27°C). I opened the jalousie window and switched on the fan. Two hours later the outside temp was up to 55°F (13°C), but the greenhouse temp had dropped to 75°F (24°C) with the fan running all that time. The next day I tried another experiment. When the greenhouse temp got up to 80°F, I turned on the fan but left the door open instead of the window. Two hours later it was down to 70°F (21°C).

All of this is very hopeful. My hoophouse ultimately failed because I couldn't vent the hot air on mild winder days, even when I uncovered both ends. Everything bolted! If I can keep it from getting too warm in the greenhouse in winter, I can hopefully delay bolting and get a nice harvest! Summer will be another matter, but I'm not planning on growing anything in the greenhouse in summer anyway.

Leigh Tate wrote: My hoophouse ultimately failed because I couldn't vent the hot air on mild winder days, even when I uncovered both ends. Everything bolted! If I can keep it from getting too warm in the greenhouse in winter, I can hopefully delay bolting and get a nice harvest!

I think this is the number one reason people give up on small greenhouses. The other approach to consider is thermal mass. A pipe from the peak blowing air through lines of concrete blocks that double as the foot paths might help (Roman hypocaust concept).

Jay Angler wrote:I think this is the number one reason people give up on small greenhouses.

I agree it's a concern, especially for conventional greenhouses. Thank heavens for permaculture! I'm getting a lot of good ideas here on Permies, also from Bill Mollison's permaculture design book.

The other approach to consider is thermal mass.

Definitely. I think that already, the house has acted as a thermal mass for most of our winter nights. For example, when it got down to 22°F (-5.5°C), the greenhouse didn't get colder than 32°F (0°C). We're planning a couple of rain catchment tanks in it too, so that should help as well. We've also talked about a RMH, but haven't figured out the details on that one yet.

A pipe from the peak blowing air through lines of concrete blocks that double as the foot paths might help (Roman hypocaust concept).

This is a really interesting idea. I will have to look into it!

Lots of progress. First, the window trims are up.



And painted



It gives the greenhouse a much more finished look, don't you think?

Next, a door to go from the house directly into the greenhouse.

The room that the greenhouse is attached to was originally called "the sun room" because it has so many windows. You can see photos at my blog of how it looked right before we moved in. Link here -> https://www.5acresandadream.com/2009/05/sun-room-my-studio.html

Replacing one of those windows with a door seemed like a good idea. We discussed which window, and finally decided on the one on the end.



We replaced the front and back windows on the sun room several years ago, and added insulation for energy efficiency. But we've waited to finish off the room until after we get the greenhouse built. Here's the window to be removed from the greenhouse side.













It's a pretty good drop down to the ground, so Dan built steps.



These were made from some of his home milled oak; 2-inch planks that had been sitting around for awhile. They can be moved for when we dig out the dirt a bit and put down a gravel floor.

I just love this door! It makes it so much more convenient, rather than having to go outside and around the back of the house to access the greenhouse. The cats love it too. They already love hanging out in the greenhouse and this door makes it easier to inform the humans that they want to go out there.